Illuminated instrument dials

ABSTRACT

The dial of an instrument such as a watch is illuminated by an electric bulb housed in an elongated tubular element of supple transluscent plastic material removably fitted about the periphery of the dial in a groove in the instrument casing or bezel ring. Sharp terminals protruding in the groove cut through the tubular element to supply the bulb via contacts in the element.

United States Patent 1 Brien [111 3,748,456 1451 July 24, 1973 ILLUMINATED INSTRUMENT DIALS [76] Inventor: Andr Brien, 3110 rue Germain,

Fabreville, Quebec, Canada [22] Filed: Dec. 27, 1971 [21] Appl. No.: 212,103

[30] Foreign Application Priority Data Dec. 28, 1970 Switzerland 19239/70 [52]. US. Cl. 240/21, 58/50 R [51] Int. Cl. G01d 11/28 [58] Field of Search 240/2.l, 2.17, 6.43,

240/6.45, 6.46, 1 EL; 58/50, 50 R [56] References Cited UNITED STATES PATENTS 12/1940 Rylsley 240/21 3/1932 Strock..... 240/217 3/1961 Wegner 240/21 x 2,480,393 8/1949 Bossert et al. 240/21 3,278,740 10/1966 Madansky 58/50 R X FOREIGN PATENTS OR APPLICATIONS 12,114 12/1965 Japan 240/21 1,079,222 8/1967 Great Britain 240/2.l

Primary Examiner samuel S. Matthews Assistant E a miner-Richard M. Sheer Atr0rney Stevens, Davis, Miller & Mosher [57] ABSTRACT 8 Claims, 2 Drawing Figures ILLUMINATED INSTRUMENT DIALS This invention relates to the illumination of instrument dials.

lt is known to provide certain instruments, for example wrist watches and pocket watches, with a miniature electric bulb for illuminating the dial, this bulb being connected by conducting wires to an electrical cell. In such watches, the bulb is generally mounted in a housing in the watch case middle at the level of the dial and under the watch glass; this arrangement has the drawback of requiring the watch to be dismantled by a qualified watch repairer when it is necessary to replace the bulb.

It is an object of the invention to obviate this drawback and to provide an improved instrument with a dial, a miniature electric bulb for illuminating the dial, and means for supplying current to the bulb. According to the invention, the bulb is therefore mounted in an element in a supple light-transmitting material, this element being removably fitted in a housing accessible from outside the instrument and located in the vicinity of the dial.

The accompanying drawings schematically show, by way of example, an embodiment of an instrument according to the invention, namely a watch. In the drawings FIG. 1 is a cross section through a watch including a dial illuminating device, this cross section being taken along line H of FlG. 2; and

H0. 2 is a partial plan view showing the illuminating device.

The watch 1 shown comprises in the middle 2 of the watch case a groove 3 surrounding the periphery of a glass 4 or other transparent covering fitted in the middle 2. The groove 3 accomodates a tubular element 5 forming a device for illuminating the watch dial 6. The element 5 is made of a supple and transparent or at least translucid material and contains a bulb 7 connected by leads 8 to electrical contacts 9 and 10 also located inside the tubular element 5. Two sharp terminals 11 and 12 respectively connected by an insulated lead 13 to the positive pole of a cell (not shown) and by the conducting mass of the watch case to the negative pole of the cell are provided protruding from the bottom of the groove 3 up to and firmly bearing against the contacts 9 and 10.

It can readily be seen that upon placing the tubular element 5 into the groove 3, the sharp terminals 11 and 12 pierce the wall of the element 5 and thus ensure supply of the bulb 7 through the contacts 9 and 10 and the leads 8. A switch, not shown, and preferably in the form of a push button device, can be mounted in the middle 2 along the lead 13 so as to enable a manual control of the illumination of the dial 6.

A bezel ring 14 is removably fitted over the groove 3 and can be easily detached, when it proves necessary to replace the bulb 7, to enable the element 5 to be extracted and substituted by a new intact tubular element 5 provided with a bulb 7, leads 8, and contacts 9 and 10 as before.

The element 5 is preferably in a transluscent synthetic plastic material which may be tinted so as to provide colored illumination. Instead of being tubular and having two distinct ends, as shown in FIG. 2, the element 5 could be annular in the form of a closed loop.

The bezel ring 14 closing the groove 3 could be eliminated, in which case the groove could have a narrow upper neck defined between an upper edge of the middle 2 and the glass 4 so as to be able to hold the element in position. Of course such a neck would have an appropriately placed widened part to allow for passage of the bulb 7.

For a watch including a date or calendar window 15 in the dial 6, the bulb 7 is advantageously disposed along the edge of the dial adjacent to the said window 15.

Instead of a fully circular groove 3, it would be possible to provide an arcuate groove around only a portion of the watch dial 6 and glass 4. Likewise, the groove 3 could be provided in a glass-retaining bezel ring rather than in the case middle.

While the invention has been specifically described with reference to watches, it is also applicable to mileage counters, speedometers, compasses, radio sets, alarm clocks and similar instruments where illumination of the dial may be required.

I claim:

1. In an instrument having a dial, a miniature electric bulb for illuminating the dial and means for supplying current to said bulb, the improvement comprising an element of supple light-transmitting material having at least a hollow portion for receiving the bulb, a housing in the instrument adjacent the dial and accessible from the outside of the instrument, said element being removably fitted in said housing, two sharp edged terminals in the housing positioned to pierce the supple material of said element when fitted in the housing, contact means within said element positioned to make contact with the terminals when the element is fitted in the housing.

2. The instrument of claim 1 including a transparent covering for the dial with an edge of the transparent covering forming a wall of the housing.

3. The instrument of claim 1 in which the instrument has a casing around the dial and the housing is an elongated groove in the casing adjacent at least part of the periphery of the dial.

4. The instrument of claim 1 in which the instrument has a casing around a dial of circular shape and the housing is an annular groove surrounding the dial, the element being an annular tubular member.

5. The instrument of claim 1 including a bezel ring, said housing being positioned adjacent at least part of the periphery of the dial and the element is an elongated tubular member.

6. The instrument of claim 5 in which said bezel ring surrounds a circular dial.

7. The instrument of claim 1 including calendar means viewable in the dial between the center and periphery thereof, said element and housing cooperating to locate thebulb at a peripheral position adjacent said calendar means.

8. An instrument comprising a dial, a hollow element made of flexible light-transmitting material, a miniature electric bulb located in said hollow element, said element being shaped as a loop around said dial, said instrument having a casing and a glass covering said dial, said casing having a circular groove around the glass and adapted to receive said hollow element, a removable bezel ring, said groove being open on the outer face of the instrument and being covered by said removable bezel ring, said groove being opened to the edge of the glass to provide a passage for light toward the dial, and sharp terminal means in said groove to pierce the element and provide current to the bulb.

* i t t t 

1. In an instrument having a dial, a miniature electric bulb for illuminating the dial and means for supplying current to said bulb, the improvement comprising an element of supple lighttransmitting material having at least a hollow portion for receiving the bulb, a housing in the instrument adjacent the dial and accessible from the outside of the instrument, said element being removably fitted in said housing, two sharp edged terminals in the housing positioned to pierce the supple material of said element when fitted in the housing, contact means within said element positioned to make contact with the terminals when the element is fitted in the housing.
 2. The instrument of claim 1 including a transparent covering for the dial with an edge of the transparent covering forming a wall of the housing.
 3. The instrument of claim 1 in which the instrument has a casing around the dial and the housing is an elongated groove in the casing adjacent at least part of the periphery of the dial.
 4. The instrument of claim 1 in which the instrument has a casing around a dial of circular shape and the housing is an annular groove surrounding the dial, the element being an annular tubular member.
 5. The instrument of claim 1 including a bezel ring, said housing being positioned adjacent at least part of the periphery of the dial and the element is an elongated tubular member.
 6. The instrument of claim 5 in which said bezel ring surrounds a circular dial.
 7. The instrument of claim 1 including calendar means viewable in the dial between the center and periphery thereof, said element and housing cooperating to locate the bulb at a peripheral position adjacent said calendar means.
 8. An instrument comprising a dial, a hollow element made of flexible light-transmitting material, a miniature electric bulb located in said hollow element, said element being shaped as a loop around said dial, said instrument having a casing and a glass covering said dial, said casing having a circular groove around the glass and adapted to receive said hollow element, a removable bezel ring, said groove being open on the outer face of the instrument and being covered by said removable bezel ring, said groove being opened to the edge of the glass to provide a passage for light toward the dial, and sharp terminal means in said groove to pierce the element and provide current to the bulb. 